1. Field of the Invention
The present invention relates to a busway fitting and, more specifically, to a busway fitting having a continuous busway fitting bus assembly wherein the bus bars are encased in an extruded support.
2. Background Information
A busway may be used to distribute power over an extended length, such as, but not limited to, through multiple floors of a building. The busway typically includes multiple busway sections each having a plurality of conductive members, or buses, disposed in an extruded housing. The housing, typically an aluminum extrusion, acts to support the bus members and to dissipate heat over most of the busway length. That is, the extruded housing is used to protect and support the bus members as the busway extends between floors. As the extruded housing substantially encloses the conductive members, the extruded housing does not generally allow for an additional bus, hereinafter a “tap bus,” that extends beyond the busway and is coupled to a load.
A busway fitting is an enclosure disposed on the busway wherein one or more tap buses may connect to the busway. The busway fitting is, typically, an elongated housing having a busway fitting bus assembly. The busway fitting bus assembly extends through the length of the busway fitting housing and includes two exposed ends on opposite sides of the busway fitting housing. The busway fitting bus assembly is coupled to a busway section at each end. The tap buses are coupled to the busway fitting bus assembly within the busway fitting housing. The tap buses are further coupled to a load.
For example, a busway may extend vertically through a multiple floor apartment building. On each floor of the apartment building there are a number of apartments. Thus, at each floor it is convenient to have a meter center with one meter coupled to the electrical system of each apartment. Each meter center is coupled to the busway at a busway fitting. For the sake of this example only, it will be assumed that an external source of power is coupled to a first busway section at the base of the apartment building. Thus, the apartment building busway includes a first busway section that is coupled at a lower end to the power source and at the upper end to a first busway fitting, and more specifically to the first busway fitting bus assembly lower end. The first busway fitting tap bus(es) is coupled to a meter center for the first floor apartments. A second busway section lower end is coupled to the upper side of the first busway fitting, and more specifically to the first busway fitting bus assembly upper end. The second busway section upper end is coupled to a second busway fitting, and more specifically to the second busway fitting bus assembly lower end. The second busway fitting tap bus(es) is coupled to a meter center for the second floor apartments. This configuration of bus section coupled to bus fitting may be repeated for each additional floor of the apartment building.
The busway fitting bus assembly typically included multiple buses. The buses typically included multiple main bus bar assemblies that were, in turn, made from multiple shorter bus bars. The bus bar assemblies were held in a spaced relation by one or more U-shaped brackets secured by bolts. These brackets provided the bracing required to support the bus bars. The multiple bus bars were further coupled to one or more heat sinks to dissipate the heat created when a current flowed through the bus members. The tap buses were also attached to the main bus bar assemblies by fasteners. The multiple buses also included a ground bus. Given the number of mechanical connections and components, the busway fitting bus assembly required time and effort to assemble.
There is, therefore, a need for a busway fitting bus assembly that uses fewer parts.
There is a further need for a busway fitting bus assembly that eliminates the need for a ground bus bar.
There is a further need for a busway fitting bus assembly that may be used in conjunction with busways which are presently installed.